Hot or Not: Subterranean Granny Flats?

This is an interesting idea if we've ever seen one: Nobbs Radford Architects has proposed that Sydney, Australia deal with its housing shortage by turning some of the city's 360,000 swimming pools into granny flats.

From an article in the Sydney Morning Herald:By 2036 more than 630,000 new homes will be needed to accommodate Sydney's population, which is expected to grow to 6 million. But instead of turning traditionally low-rise suburbs into vast stretches of apartment blocks, part of the growth could be housed within some of NSW's 360,000 swimming pools, Alison Nobbs said.